Explicitly specify -? as an option in tred

diff --git a/cmd/tools/tred.c b/cmd/tools/tred.c
index 386b1f23d4aafd24d4c38f125e7aa80eb25f96ec..4fec5e874b99c1ca65808d1b7b6bafe8f92b86ab 100644 (file)
--- a/cmd/tools/tred.c
+++ b/cmd/tools/tred.c
@@ -248,7 +248,7 @@ static void init(int argc, char *argv[])
 
     CmdName = argv[0];
     opterr = 0;
-    while ((c = getopt(argc, argv, "vr")) != -1) {
+    while ((c = getopt(argc, argv, "vr?")) != -1) {
        switch (c) {
        case 'v':
            Verbose = 1;
@@ -257,7 +257,7 @@ static void init(int argc, char *argv[])
         PrintRemovedEdges = 1;
         break;
        case '?':
-           if (optopt == '?')
+           if (optopt == '\0')
                usage(0);
            else {
                fprintf(stderr, "%s: option -%c unrecognized\n",